Forced-draft furnace.



No. 718,779. 7 PATBNTBD JA-N.20,1903.

' F. J. MALY.

FORGED DRAFT FURNACE.

APPLICATION FILED JAN. 14, 1902.-

I0 MODEL.

v FlGi UNITED STATES PATE T OFFICE,-

FRANZ JOSE-F 'MALY, OF Aussie, AUSTRIA-HUNGARY.

FORQEID-IDRLA'FT, FURNACE,-

SPEGIFIQAIJQON forming part of Letters Patent No. 718,779, dated January 20, 1903. Application flled-Isnuaryl i,1902- Serial No. 89,779. (NoinodeL) To all whom it may concern:

Be it known that I, FRANZ J osEF subject of theEmperorof Austria- H ngary, residing at Aussig, Bohemia, Austria-Hun- 5 gary, have invented certain new-and useful Improvements in Forced-Draft Furnaces; and I do hereby declare the following to be a' full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to makeand use the same. My invention relatesto improvements in forced-draft furnaces which are especially adaptedfor locomotives,but may with the same effect be employed'inothermovable (for .ins'ta nce, marine boilers) and also stationary boilers. In the accompanyingdrawiugs,'which illustrate two different modifications of the invention, Figure 1 is longitudin 2o fire-box and the-adjacent tive-boilenf Fig; 2j-is partly section, partly a side elevafie mode of construction (if; V, is a cross-section on th'e'li'ne z 5 Fig. 4 is anothercross-sec line C D, Fig. 2. I Manyt'rials have been made. to i'mpr' Y combustion of fuel in steam-boilers'by'leading a. part of .the products of combustioniback to the fire; but these trials could not have theexpectedresnlts, as the manner in-which the i smoke and eventually thesteam mixed therewith were forced into the-fire eifected for the high amount of heat necessary forthe dissociationof the smoke and steam a-considerable cooling of the burning fuel ,on-the grate or gas stream rising from it. This cooling of the whole fire, by. which theprocess of j combustion becsmefgreatly disturbed,- and 9: furthermore"? much smoke was produced,

erselfmice: by leadiiig back-drivenis'uio'ke' net directlyfinitoth box above thefu'eh'. hilt first intothe sh-i'pit, where it becomes kedg'with the airtto bedriVeni th-I' ughthe' after' -this'.-a;irfhes"in sun 7 a d marten; that the m1. jmnst'rgive hot air,smoke',a iidstesmisstresminfithroug the fuel into the fire-box; peratnre of the mixture passing through the tionof the voided by thew-present f ar th n bbaok; Adj-projects, as shown in Fig. 1, hori ,zontallyizito th'e'ash-pitn At a suitable point "asteam-ho'zzlek is provided within thissmoketube obtain a better distribution and (agree been 4 .onlyiaismall' .5 {part of the 'i'q'uired'fdissociationlheat of the smoke and steam-when the'mijxt'iire of verg For the high temfuel on the, grate the-burning process of the gases, fresh developed within the fuel and rising from it will not be disturbed, and said mixture of gases after being, during its passing through the layer of f as], dissociated will again combust with a long flame, and from this whole quantity of entirely-burned gases which ,now rise up through the fire-box that amount of heat in an innoxious manner-that is, without reducing the economical effect of the furnace-can be taken which is required to'highly heat the fresh air to be mingled with the back-driven smoke and the steam, a furnace working in-such a manner being particularly suitable for employing anthracite, coke, and other similar fuel, developing, respeotively, only small quantities of gas and burning with short flames.

' In the annexed drawings, showing furnaces which'act in this generally-described improved manner, like letters of reference refer to like parts ofcc'onstruction.

, Below the horizontal cylindrical part of the boiler several air-tubes a are provided, which feed the fire with 'air, and for this purpose contain steam-nozthe necessary quantity of 'zlesb, in the construction of the furnace shown'byFig. 1 this. air being led into a respectively large hollow fire-bridge. c, in which it; becomes very highly heated. In order to accomplish, this, the fire-bridge has a partition-d, by which-it is divided intotwo spaces f and e, of which the former is in open connection with the air-tubes a, and the latter with the ash-pit g. The air sucked by the steam-nozzles 7) into the tubes a is forced upward through the space f, then downward through the space e, from here into the ashpit,'aud finallyin the well-known manner through the grate h and the fuel on the same.

,The leading back ofone part of the smoke from thesmoke-boxy to the ash-pit g is efpfectedi hy means of a-tobe z, the which "extends upward to about the center of front endof oke;box, f(s ee also Fig. 2,) whilethe mlxing of the smoke with the air ssh-pit, a wedge or the month-of the tube a.

within the cone loan be located at The very highly heated n :ture of air, smoke, and steam passes through the fuel on the grate It, whereby the smoke will at first be employed, without driving reduced to carbonic oxid and the steam dissociated into hydrogen and oxygen, whereupon these gases when passing through the uppermost hot red fuel .become again burned to carbonic acid and steam-shaped watertha,t' is,in the present case,to saypyerheated steam. These gases, as well as those fresh developed from the fuel, will now in shape of long flames draw through the fire-chamber around the upper edge of the fire-bridge c and then through the smoke-tubes m, leaving within these latter a larger part of their heat than heretofore, when only short-flamed fuel was back one part of the smoke.

The construct-ion of the present furnace (shown by Figs. 2 to 4) is different from that already described in as far as the fire-bridge has been built up ina modified manner, also the wedge-like part I is being replaced by a tube 0, being across secured to the tube 1' and having a great number of small openings or, through which the smoke can enter the ash-pit. The whole fire-bridge, together with its, oblique -arranged tong-like upper part, consists of only one casting 0, being covered with a thin layer of fireproof material 1* and containing three air-channels 19, each of which being, as shown in Figs. 3and 4, formed by fourshorter channels, through which the air, as indicated by arrows, passes two times. up and down, so as to finally enter the ashpit through the three openings q. As these openings q are about regularly arranged over the entire breadth of the ash-pit, a good distribution of the smoke and mixing of it with the extremely highly heated air are eifected, and the long flames produced in the furnace will rise from the entire surface of the grate.

Because-the whole quantity of air required. by the fuel burning on the grate is forced through the channels 19 the casting forming the fire-bridge c is very etfectively protected against too early wearing out. Near its up"- per edge the fire-bridge may be provided'with a number of small openings, by means ofwhich a little portion of the hot air in the direction of-the arrows to directly streams into the flames passing through the fire-chamber. In employing the present furnace in locomotives it will be useful to extend the blastpipe up to the upper edge of the funnel of the locomotive to prevent the smoke-box from being, as usual in the common locomotives, evacuated, as such a partial evacuationof the smoke-box would in the presentcase make it heavier to the steam-nozzles to force the smoke back to the ash-pit. As the air becomes by means of steam-nozzles pressed into the ash-pit, it is not necessary to produce a partial vacuum within the smoke-box, and,

'furthermore, fuel is also saved for the reason of the locomotive expand to nearly the pressure of the atmosphere. I

The gases will in the present furnace leave the smoke-tubes m with comparatively high temperature. This can' be used'for heating the feed-water of the boiler. For this purpose in the smoke-box y of thelocomotive a spiral tube .2 is provided, the outer end of .which is connected with the injector, while the other end will leadthe heated water into the boiler. This spiral tube or another similar arrangement may be employed for super-.

heating the steam working of the machine.

What I claim, and tore Patent, is-' v 1. In a forced-draft furnace, the combination with a grate, of a hollow bridge-wall having its upper end deflected laterally and projectingover the grate and its interior commuin the cylinders desire to protect by Lotnicating with the space below the grate, a series of openings in the lower or forward face of said deflected portion of the wall, and means for supplying air to the interior of the deflected portion of said wall.

2. In a forced-draft furnace, a bridge-wall whose upper end is, deflected laterally and projects over the grate and which is provided with a series of interior passages each extendmg throughout the length of the deflected p'ortion of 'said wall and communicating at one end with an air-supply and at the other end withthe space beneath the grate.

3., In a forced-draft furnace,a bridge-wall provided with a series of independent interior passages each communicating at one end with an air-supply and at the other end with the space beneath the furnace-grate, and each ofsaid passages extending laterally over the furnace-grate and being exposed to thedirect action of heat arising from fuel on the grate, air entering said passages being compelled to travelthrou'ghout the length of the laterally-projecting sections thereof.

4. In a forced-draft finance, the combination with a grate'of a bridge-wall consisting EPaseries of hollow sections, each having its upper end projecting over the grate, partitions dividing the interiorof each of said sec tions into two passages that communicate at the upper end of the section, one of said passages communicating with the space-beneath the furnace-grate, and means for supplying air to the other saidgassage in each section.

too

5. In a forced-drafttnrnace,the combin,a-.

tion witha grate, of a bridge-wall consisting of a series of hollow sections arranged side by side,"partitions dividing each of said sections into two passages communicating at the upper ends, said sections being arranged in pairs and similar passages in the sections of each pair being connected, at their lower ends, the other passage in one of the sections of each pair communicating with the space below the furnace-grate, and means for supplying air to the corresponding passage in the other section of each pair.

6. In a forceddraft furnace, the combination with agrate; of a hollow bridge-wall hav-e ing its upper end deflected and projecting over the grate, the interior of said wall being divided into a series of passages, each extending from the lower rear end of the bridge-wall to the top thereof and from said top to the lower-front end of thewall, and communicating at said front end with the space beneath thgfl rnace andat an intermediate point of its 1 mgth with the furnace above the grate,

" and means for supplying air to the rear end of said passage. 4 7 In a forced-draft furnace, the combination with a grate, and a series of fire-tubes,

of a hollow bridge-wall having its-upper end terminating above the lower plane of the se ries-of fire-tubes and deflected laterallyto project-over the grate, the interior of said bridge-Wall communicating with the space 'beneath'the grate, means for supplying air to the interior of the deflected portion of said bridge-wall, and'means for conveying a portion of the products of combustion from beyond the discharge ends of the fire-tubes to the space beneath the fnrnace-grate.

-In testimony whereof I affix my signat n're 

